Hello, at the moment, I am not able to replicate the results posted. Explain analyze results are very similar at the moment on both databases, query runtime is also almost same. This has happened after re-running VACUUM ANALYZE VERBOSE. However, right after the migration, I did run the script, which was generated by pg_upgrade script, which should have ran VACUUM on the database, the script name is analyze_new_cluster.sh. Maybe after re-running vacuum analyze the statistics somehow changed?
Case closed, thank You. -- Matúš Svrček PlainText s.r.o. [www.plaintext.sk] svr...@plaintext.sk ----- "Victor Yegorov" <vyego...@gmail.com> wrote: > 2014-09-26 17:04 GMT+03:00 Matúš Svrček < svr...@plaintext.sk > : > > > I am having a performance issue after upgrade from 8.4.20-1 -> 9.3.5. > > > First, make sure you have your statistics up to date — execute manual > `VACUUM ANALYZE`. > And then provide `EXPLAIN analyze` for 8.4 and `EXPLAIN (analyze, > buffers)` for 9.3 output. > > > > -- > Victor Y. Yegorov -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
